The word Unfirmnes is misspelled against Unfirmness, a noun meaning "Infirmness."
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Unfirmness has double 'ss' in the end mispronounced as 's'
Remember double 'SS' appears in the end of this word which should not be misspelled with single 'S'
Wrong Spelling: unfirmne-s
Correct Spelling: unfirmne-ss
Find more wrongly spelled words of Unfirmness to spell it well.